A urostomy pouch or bag of the type exemplified by co-owned U.S. Pat. Nos. 3,523,534 and 3,822,704 is capable of being worn continuously by a patient for several days or more before being removed and replaced by a fresh pouch. During the period of continuous wear, such a pouch must be periodically drained of its fluid contents by manipulating a drain valve at the pouch's lower end. While periodic draining is a necessary and acceptable inconvenience during hours while the wearer is awake, it is an objectionable inconvenience during hours of rest.
Drainage pouches are currently available which are designed to be coupled to drainage tubes leading to relatively large volume bedside containers, thereby permitting exudate to drain continuously through the pouches into the containers so that the user's sleep need not be interrupted by the necessity of periodically emptying the contents of the pouches. While sound in principle, such arrangements have not been entirely successful in practice because of a variety of problems, including difficulties in manipulating the valves and couplings, and tendencies to wear rapidly and leak in use, or to obstruct flow and cause distension and possible rupture of the pouches. There is also the risk that excessive force applied during manipulation of a valve, or in coupling or uncoupling a drainage tube, may impose undue strain on the walls of the drainage pouch, resulting in tearing of the pouch and leakage of its contents. Such risks may be increased if the fittings of the pouch are blocked from direct view by the user, or where the user suffers from some condition or disease, such as arthritis, which makes manipulation of the valve and coupling more difficult.
More specifically, current drainage pouches are sometimes equipped with soft plastic drainage nozzles equipped with removable caps of the same material. When a drainage tube is to be connected, the cap is simply removed, a separate connector is attached to the nozzle, and the tube of the drainage set is then coupled to the connector. Although such a nozzle construction has the advantages of softness and flexibility, thereby reducing the possibilities of pouch rupture, manipulative difficulties exist and are increased by the need for an additional part (connector). Also, experience indicates that such constructions are more prone to leakage over periods of extended use.
In another type of commercially-available construction, the drainage pouch is equipped with a sleeve valve designed to be operated by sliding one telescoping part with respect to another part. While such a valve is advantageous in terms of ease of operation, the act of coupling the valve to a drainage tube is more difficult. Also, because such a construction involves the provision of relatively small flow passages through the valve, such passages have a tendency to be clogged by the more viscous components (e.g., mucus) of the exudate. Where such problems are likely to arise, users are instructed to disassemble the valves prior to attachment of the drainage tubes, such disassembly thereby increasing the complexities and likelihood of user problems, including loss of parts, in performing the manipulative steps.
Accordingly, it is an object of the present invention to provide a drain assembly for a urostomy pouch which overcomes the defects and disadvantages of prior drain assemblies. Specifically, it is an object to provide a drain valve which is easily operated even when out of the user's line of sight, is highly effective in blocking the flow of fluid when adjusted into a closed position, even after periods of extended use, cannot be manipulated to produce inadvertent disassembly of the valve elements, is not likely to obstruct flow (because the passages through the valve are of a cross section at least as large as the drainage tube), and is constructed so that even if excessive force and/or improper technique are used to manipulate the valve, the possibilities of failure of the assembly or damage to the drainage pouch to which the assembly is connected are non-existent or at least extremely remote.
A further object is to provide a drain assembly which includes a drainage tube equipped with a coupler which may be easily and effectively operated to attach the tube to the hollow stem of the valve and to disconnect the tube from that stem. Despite the ease with which the coupler may be operated to latch or unlatch it from the stem, such coupler forms a highly effective leak-resistant seal with the stem and coacts with the stem to produce a secure latch capable of resisting disengagement by all forces exerted on the drainage tube that might be expected to develop during use of the assembly. In addition to greater effectiveness of operation, the coupler, as it is slipped into latching position, coacts with the valve stem to produce an audible snap or click to assure the user that the parts are latched securely together.
Briefly, the drain assembly comprises a body member adapted to be mounted within a urostomy pouch at the lower end thereof, a tubular valve member rotatably connected to the body member, and a drainage tube equipped at one end with a coupler for releasably engaging the tubular stem of the valve member. The body member has walls defining a generally cylindrical discharge chamber, such chamber having a side opening and a lower end opening. The valve member includes a sleeve portion which is rotatably received within the chamber of the body member through the lower end thereof, such valve member also having an open-ended tubular stem which projects downwardly below the body member. The sleeve portion of the valve member has a lateral port which is registrable with the side opening of the body member when the valve member is rotated into an open position, such lateral port being out-of-register with such side opening when the valve member is rotated into a closed position. Locking means secures the body and valve members against axial displacement without at the same time preventing relative rotation of the parts.
Each of the body and valve members is formed of a semi-rigid plastic material, the plastic of the valve member being more rigid (or less flexible) than that of the body member. An integral bead is formed about the lateral port of the valve member and forceably engages the more yieldable material of the body member to produce a highly effective primary or internal seal. A secondary or external seal is formed between an annular flange at the lower end of the body member and the more rigid material of the valve member, such contact occurring within an annular upwardly-facing channel formed in the valve member about the sleeve portion thereof.
The body member also includes a pair of diametrically-disposed lateral extensions, such extensions having side surfaces which extend along converging planes and which terminate in lateral edges substantially parallel with the axis of the body member. In addition, the body member includes a top wall which merges with such lateral edges to form corners, and a pair of thin flexible stress-relieving tabs which are formed integrally with the body member and which project radially and upwardly from such corners.
The tubular stem of the valve member is provided with an annular shoulder spaced above the stem's open lower end, such shoulder having an upwardly-facing latching surface and a downwardly and inwardly inclined camming surface. The coupling means of the drainage tube takes the form of a flexible tubular connector which is secured to the drainage tube and dimensioned to sealingly receive the lower portion of the valve stem. Such coupling means also includes latching means in the form of a flexible oval latching ring extending along a plane normal to the axis of the tubular connector and joined thereto by a pair of flexible arms. Normally the flexible ring assumes an oval configuration in which its minimum inside diameter approximates the outside diameter of the stem and is less than the greater diameter of the latching shoulder; however, when finger pressure is applied to opposite ends of the oval latching ring, such ring may be temporarily reformed or distorted into a generally circular configuration in which its inside diameter exceeds the diameter of the shoulder, thereby permitting the coupler to be removed from the stem of the valve member.
Other advantages, objects, and features of the invention will become apparent from the specification and drawings.